Understanding the dynamic response of soil is crucial in geotechnical engineering. Based on the Biot's theory of poroelastic soil, the integral transformation method is used to solve the wave equation of multilayered poroelastic soil. Analytical solutions for the dynamic displacement and stress fields in the spatial domain are then derived. This method accounts for the transverse isotropy properties and the discontinuous contact conditions between adjacent layers. The accuracy of the algorithm is verified by the degradation models. On this basis, the effect of varying interlayer contact parameters on the displacement fields of the poroelastic layered soil is examined. The results show that the interlayer discontinuity condition state significantly affects the dynamic response, with a greater degree of separation leading to a greater dynamic displacement response and increased susceptibility of the pavement to damage. Finally, an example is given to analyze the effect of heterogeneous properties of soil on the dynamic response of multi-layered system. Due to the existence of discontinuous contact between layers, the influence of the heterogeneous properties of the soil on the dynamic response of the pavement structure is weakened, but it still has a great influence on the soil below the discontinuous contact layer.
